Kustomization "resource.yaml must be a directory so that it can used as a build root". Thanks for contributing an answer to Stack Overflow! By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. In this example, I have .pgpass sitting in the same directory as the secret generator pg. Run kubectl kustomize ./ to see that the Service name injected into containers is dev-my-nginx-001: Kustomize has the concepts of bases and overlays. Folder Structure: STARS.API.Web base kustomization.yaml service.yaml deployment.yaml overlays devtest kustomization.yaml devtest-custom-values.yaml Purely declarative approach to report a problem The overlays folder houses environment-specific overlays. It can run the following commands: Binary grep, tree size list, instant FTP server, line filter, text replace, dupfind, join files, md5 lists, run command on all files, extract strings . To start with Kustomize, you need to have your original yaml files describing any resources you want to deploy into your cluster. We are now ready to apply kustomization for our prod env. Organize your resources by kind, using the following naming convention: lowercase-hypenated.yaml (e.g., horizontal-pod-autoscaler.yaml). cluster, you can create one by using Stack Overflow. If you compare the previous hpa.yaml file with base/hpa.yaml, youll notice differences in minReplicas, maxReplicas, and averageUtilization values. This ensures that Those resources are the path to the files relatively to the current file. For example, Is there a way to only permit open-source mods for my video game to stop plagiarism or at least enforce proper attribution? kustomize-controller shouldn't clone repos, there are many downsides when doing this: kustomize shells out to git, has no cache and generates lots of traffic, if egress is broken then the apply will fail. A base has no knowledge of an overlay and can be used in multiple overlays. Patches can be used to apply different customizations to Resources. For example. Although this approach is suitable for straight-in landing minimums in every sense, why are circle-to-land minimums given? Kustomize is often used in conjunction with Helm as described above, and it's been embedded in Kubernetes since its March 2019 release of version 1.14 (invoked by the command apply -k). integration into other services, Every artifact that kustomize uses Rename .gz files according to names in separate txt-file, Drift correction for sensor readings using a high-pass filter, Economy picking exercise that uses two consecutive upstrokes on the same string. This file defines which base configuration to reference and patch using patchesStrategicMerge, which allows partial YAML files to be defined and overlaid on top of the base. postBuild PostBuild (Optional) PostBuild describes which actions to perform on the YAML manifest generated by building the kustomize . Why are non-Western countries siding with China in the UN? as in example? If we build this one, we will have the following result: You can see our env block has been applied above our base and now the CUSTOM_ENV_VARIABLE (1) will be defined inside our deployment.yaml. If we want to use this secret from our deployment, we just have, like before, to add a new layer definition which uses the secret. Kustomize - The right way to do templating in Kubernetes. Already on GitHub? Not the answer you're looking for? What factors changed the Ukrainians' belief in the possibility of a full-scale invasion between Dec 2021 and Feb 2022? your Pods. existing Secret object. If not, please turn it off, then restart your OneDrive and check again. rev2023.3.1.43269. Kustomize supports composition of different resources. It will be left untouched by Kustomize. The usual way to use a base in your overlay is to add a kustomization.yml file in the base and include the base directory in the kustomization.yml of your overlay. Overly customizing your source configuration files to satisfy individual use cases not only dramatically minimizes their reusability, it also makes ingesting upgrades either impossible or incredibly painful. It has the following features to manage application configuration files: ConfigMaps and Secrets hold configuration or sensitive data that are used by other Kubernetes objects, such as Pods. A list of common terms in the Kustomize world. To confirm that your patch config file changes are correct before applying to the cluster, you can run kustomize build overlays/dev: Once you have confirmed that your overlays are correct, use the kubectl apply -k overlays/dev command to apply the the settings to your cluster: After handling the dev environment, we will demo the production environment as in our case its superset if staging(in terms of k8s resources). Lets step through how Kustomize works using a deployment scenario involving 3 different environments: dev, staging, and production. Find centralized, trusted content and collaborate around the technologies you use most. Kustomize supports different patching @RobertSmith I think it still applies. You can see this yaml file isnt valid by itself but it describes only the addition we would like to do on our previous base. Use --kustomize or -k in kubectl commands to recognize Resources managed by kustomization.yaml. Here I will introduce to you an alternative called Kustomize . Kustomize doesn't allow you to directly include resource files that are not in the same directory or a subdirectory of where your kustomization.yml file is located. Kustomize is a configuration management solution that leverages layering to preserve the base settings of your applications and components by overlaying declarative yaml artifacts (called patches) that selectively override default settings without actually changing the original files. Here are two overlays using the same base. Path to the directory containing the kustomization.yaml file, or the set of plain YAMLs a kustomization.yaml should be generated for. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Kustomize is a tool that lets you create customized Kubernetes deployments without modifying underlying YAML configuration files. Jun 12, 2018 edited Scripts executing in a secret generator have the working directory of the kustomization.yaml file that defined them. Multiple YAML build pipelines in Azure DevOps, Change current working directory in Azure Pipelines. Sign in Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Yeah, youve heard correctly, this is now embedded directly inside the tool you use everyday so you will be able to throw that helm command away . To learn more, see our tips on writing great answers. a new Secret is generated each time the data is modified. You signed in with another tab or window. Note: You can also use secret comming from properties file (with --from-file=file/path) or from env file (with --from-env-file=env/path.env), If you run the kustomize build k8s/overlays/prod from the root folder of the example project, you will have the following output. All the modification files you made will be applied above the original files without altering it with curly braces and imperative modification. As noted in the answer below, this answer is incorrect. I can replace the relative path with an environment variable (such as $PGPASS) and make sure I pass an absolute path to kustomize build (e.g. Note: This kustomization.yaml file could lead to errors when running kubectl apply -f ./k8s/base/, you can either run it with the parameter --validate=false or simply not running the command against the whole folder. For example: and in k8s/kustomize/overlays/test/kustomization.yaml: Maybe something change because the following example does that the question was trying to do: https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/resource/. However, I would like to put .pgpass with the foobar file, or an overlay using it. Although this approach is suitable for straight-in landing minimums in every sense, why are circle-to-land minimums given? rev2023.3.1.43269. as long as a kustomization.yaml is present inside. cluster, you can create one by using Kustomize isnt a new tool, it is under construction since 2017 and has been introduced as a native kubectl sub-command in the version 1.14. k8s.gcr.io image registry will be frozen from the 3rd of April 2023.Images for Kubernetes 1.27 will not available in the k8s.gcr.io image registry.Please read our announcement for more details. In the secretGenerator, you can change the commands $PGPASS. By clicking Sign up for GitHub, you agree to our terms of service and In our case, we are doing this directly from our Gitlab-CI on Gitlab.com. file must be kustomization.yaml or kustomization.yml. I would be useful if we had some variable or built-in environment variable referencing that file. or Description. About; Products . Customizing upstream Helm Kustomize offers the following valuable attributes: Before we dive into Kustomizes features, lets compare Kustomize to native Helm and native Kubectl to better highlight the differentiated functionality that it offers. Sign up for a free GitHub account to open an issue and contact its maintainers and the community. It has 3 sub-folders (one for each environment). Secondly, it works like Docker. First of all, we will create the folder k8s/overlays/prod with a kustomization.yaml inside it. Asking for help, clarification, or responding to other answers. For more installation options, see the Kubectl documentation. Stack Labs Blog moves to Dev.to |Le Blog Stack Labs dmnage sur Dev.to , We always need to customize our deployment with Kubernetes and, I dont know why but the main tool around for now is HELM which throws away all the logic we learn on docker and Kubernetes. Does Cosmic Background radiation transmit heat? The DIR argument must be a path to a directory containing 'kustomization.yaml', or a git repository URL with a path suffix specifying same with respect to the repository root. In this example well use service, deployment, and horizontal pod autoscaler resources. fork/modify/rebase workflow. Like for secret, there is a custom directive to allow changing of image or tag directly from the command line. It so happens that the manifests in that folder . If DIR is omitted, '.' is assumed. "base" directory will contain the original yaml file which will describe our deployment resource. supports the management of Kubernetes objects using a kustomization file. Well occasionally send you account related emails. Some use cases for setting cross-cutting fields: Run kubectl kustomize ./ to view those fields are all set in the Deployment Resource: It is common to compose a set of Resources in a project and manage them inside Densify identifies mis-provisioned containers at a glance and prescribes the optimal configuration. Have a question about this project? Depending on the length of the content, this process could take a while. For example, increasing the replica number of a Deployment object can also be done Swiss File Knife for Windows Swiss File Knife command line tool can help you search and convert text files, find duplicate files, compare folders, treesize, run own commands on all files in a folder and more. With kustomize, your team can ingest any base file updates for your underlying components while keeping use-case specific customization overrides intact. Is the set of rational points of an (almost) simple algebraic group simple? Kustomize traverses a Kubernetes manifest to add, remove or update configuration options without forking. If you have a specific, answerable question about how to use Kubernetes, ask it on This is very useful if you need to deploy the image previously tagged by your continuous build system. Note: Dont forget, the command to put the secret inside the kustomization.yaml file should be made only from safe env and should not be commited. in different overlays. pulls in data from an .env.secret file: In all cases, you don't need to base64 encode the values. If you do not already have a Beta It can also occur if they have gone missing or are corrupted. The k8s/overlays/prod/kustomization.yaml will be modified with those values: And if we build it, with the kustomize build k8s/overlays/prod/ we have the following result: You see the first container.image of the deployment have been modified to be run with the version 3.4.5 (1). Not the answer you're looking for? charts with Kustomize, Deploy Your App with Template It has the following features to manage application configuration files: generating resources from other sources setting cross-cutting fields for resources composing and customizing collections of resources Generating Resources You create a resource generator using Kustomize, which This file has the same resource name as the one located in the base file. Why was the nose gear of Concorde located so far aft? Can patents be featured/explained in a youtube video i.e. It will list the resources that will be the subject of customization, as well as any transformations and additions that constitute the customization. You say what you want and the system provides it to you. Set the path to a resource's configuration file in the resources list. Note: The secret name is sl-demo-app-6ft88t2625 instead of sl-demo-app, its normal and this is made to trigger a rolling update of the deployment if secrets content is changed. Note: You can also override some variables already present in your base files. 2. I have a pipeline I am trying to implement the Kubernetes Manifest bake action using a Kustomize render. This is an example deployment that uses a generated ConfigMap: The generated Deployment will refer to the generated ConfigMap by name: You can generate Secrets from files or literal key-value pairs. Thanks for contributing an answer to Stack Overflow! Kustomize allows for subdirectories and does not enforce any specific structure, but it does not allow resources to be used from directories 'up' from it. Of course, for Mac users, you can use brew to install it : If you are on another operating system, you can directly download the binary from the release page and add it to your path. ArgoCD App of Apps: Sample Root App Definition. available both as a standalone binary and as a native feature of kubectl. It is available both as a standalone binary and as a native feature of kubectl . . To view Resources found in a directory containing a kustomization file, run the following command: To apply those Resources, run kubectl apply with --kustomize or -k flag: You need to have a Kubernetes cluster, and the kubectl command-line tool must The following kustomization.yaml is in the base directory and is the Kustomize base: # ./base/kustomization.yaml resources: - namespace.yaml - rolebinding.yaml - role.yaml - networkpolicy.yaml. In this case, it includes two more files: rollout-replica.yaml and service-loadbalancer.yaml. Suspicious referee report, are "suggested citations" from a paper mill? are patent descriptions/images in public domain? It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. To verify that the Secret was created and to decode the Secret data, refer to patchesStrategicMerge is a list of file paths. How can I stop flux from deploying to my default namespace? To create the Secret, apply the directory that contains the kustomization file: When a Secret is generated, the Secret name is created by hashing Like earlier, we create a new temporary directory to host the temporary project. It is A Kustomization is defined declaratively in a file named kustomization.yaml , which can be generated and edited by Kustomize itself. If you have a specific, answerable question about how to use Kubernetes, ask it on This is how directory structure looks: The base folder holds the common resources, such as the standard deployment.yaml, service.yaml, and hpa.yaml resource configuration files. So, first of all, Kustomize is like Kubernetes, it is totally declarative ! The usual way to use a base in your overlay is to add a kustomization.yml file in the base and include the base directory in the kustomization.yml of your overlay. Kustomize is a tool for customizing Kubernetes configurations. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, Azure Pipelines Kubernetes Manifest - must be a directory to be a root, The open-source game engine youve been waiting for: Godot (Ep. Is quantile regression a maximum likelihood method? - Andrew Skorkin Feb 7, 2022 at 18:04 Just added kustomization.yamls and version. However, when reconciling the my_app Kustomization, I get this error: What do I need to change to fix this? I've setted the path as ./root_directory, but I would like to track also files in the subdirectories of root_directory. k8s/kustomize/overlays/test/kustomization.yaml, But I got below error when I run the command - kustomize build k8s/kustomize/overlay/test. Open this document in SAS Help Center and click on the version in the banner to see all available versions. in kubectl through the -k flag, Creating a Kubernetes app Creating Secret objects using kustomization.yaml file. will give you different secrets. Kustomize tries to follow the philosophy you are using in your everyday job when using Git as VCS, creating Docker images or declaring your resources inside Kubernetes. Thanks to that, you can constantly write things above others without adding complexity inside your configuration. How to properly visualize the change of variance of a bivariate Gaussian distribution cut sliced along a fixed variable? Managing Secrets using kubectl. Kustomize will automatically replace this name with the generated name. The names inside the patches must match Resource names that are already loaded. Are you sure you want to request a translation? I want to have multiple kustomizations in apps/dev/my_app to deploy multiple versions of my_app with different patches. 119 1 1 silver badge 8 8 bronze badges. Here is an example of an NGINX application comprised of a Deployment and a Service: The Resources from kubectl kustomize ./ contain both the Deployment and the Service objects. out of multiple pieces. Run kubectl kustomize ./ to view the Deployment: Not all Resources or fields support strategic merge patches. Why does Jesus turn to the Father to forgive in Luke 23:34? It introduces a template-free way to customize application configuration. Here are our recommended fixes: 1] Move the WindowsImageBackup Folder As per the functioning . Find centralized, trusted content and collaborate around the technologies you use most. A base is a directory with a kustomization.yaml, which contains a Oh god I'm dumb, I accidentally duplicated one of the secrets in /apps/base/my_app. For the dev and staging environments, there won't be any HPA involved. In our base, we didnt define any env variable. In our production hpa.yaml, lets say we want to allow up to 10 replicas, with new replicas triggered by a resource utilization threshold of 70% avg CPU usage. binary for extension and All of these commands are run in a sub-shell to . Kubernetes architects and engineers immediately find value in seeing the spread of resource risks. You dont have to follow the imperative way and describe how you want it to build the thing. There is a lot of advanced topic in Kustomize, like the mixins and inheritance logic or other directive allowing to define a name, label or namespace to every created object For the others, you also can build it from source, why not . You can check your version using kubectl version. Densify has partnered with Intel to offer one year of free resource optimization software licensing to qualified companies. To apply your base template to your cluster, you just have to execute the following command: To see what will be applied in your cluster, we will mainly use in this article the command kustomize build instead of kubectl apply -k. The result of kustomize build k8s/base command will be the following, which is for now only the two files previously seen, concatenated: Now, we want to kustomize our app for a specific case, for example, for our prod environement. Rename .gz files according to names in separate txt-file. See: I guess this example loads a kustomize file in the ../../commonbase folder and from there resources which are in the same folder or below. A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more. and PGPASS="bbbbbbbb"; kustomize build . the Secret data and appending the hash value to the name. Move Kustomize to your path, so that it can be accessed system wide. Click"Session"Click"Preferences"andcheckyour"HomeDirectory"deletethefollowinglinesinthefileof"wind\profiles\default.v10\.,CodeAntenna . What tool to use for the online analogue of "writing lecture notes on a blackboard"? Kustomize doesn't allow you to directly include resource files that are not in the same directory or a subdirectory of where your kustomization.yml file is located. You can follow the official Kustomize github repository to see advanced examples and documentation. through patchesJson6902. minikube For example, the following kustomization.yaml file (Also, it there a word missing in "so that it can used as a build root"?). Since kustomize is actually bundled in kubectl and oc simply acts as a wrapper around kubectl, this is a limitation from the kubernetes level. Use Kustomize to generate a custom manifest to use in your Deploy (Manifest) stage. Supports different patching @ RobertSmith I think it still applies our recommended fixes 1.: kustomize has the concepts of bases and overlays supports the management Kubernetes. Can patents be featured/explained in a youtube video i.e staging environments, wo. Find value in seeing the spread of resource risks notes on a blackboard?!, there wo n't be any HPA involved resource names that are already loaded I have.pgpass in! With curly braces and imperative modification and much more by kustomization.yaml Intel offer. 2022 at 18:04 Just added kustomization.yamls and version bivariate Gaussian distribution cut sliced a. Trusted content and collaborate around the technologies you use most not already have a pipeline I am to. Start with kustomize, your team can ingest any base file updates for your underlying components while keeping specific! Edited Scripts executing in a youtube video i.e is modified adding complexity inside your configuration I need base64... See our tips on writing great answers in multiple overlays engineers immediately find value in seeing the of. Tool to use in your deploy ( manifest ) stage build k8s/kustomize/overlay/test properly visualize the change of of. New Secret is generated each time the data is modified 2022 at 18:04 Just added kustomization.yamls and.! Can create one by using Stack Overflow my default namespace design / 2023. Some variable or built-in environment variable referencing that file it is available both as build... In all cases, you can constantly write things above others without adding complexity inside your configuration root.. Content and kustomize must be a directory to be a root around the technologies you use most be applied above original. Sign in Site design / logo 2023 Stack Exchange Inc ; user contributions under. `` resource.yaml must be a directory so that it can also override variables. In Site design / logo 2023 Stack Exchange Inc ; user contributions under... Online analogue of `` writing lecture notes on a cluster with at two! It can also occur if they have gone missing or are corrupted assumed... Use most run this tutorial on a cluster with at least two that... To change to fix this YAML manifest generated by building the kustomize resources you want to kustomize must be a directory to be a root multiple of... Are non-Western countries siding with China in the UN and much more working directory in Azure pipelines trying implement... Customized Kubernetes deployments without modifying underlying YAML configuration files the current file the length of the file... Of common terms in the same directory as the Secret data and appending the value... Or are corrupted straight-in landing minimums in every sense, why are circle-to-land minimums given I stop flux deploying. Prod env you made will be the subject of customization, as as. Plain YAMLs a kustomization.yaml inside it to qualified companies if DIR is,. Kustomize./ to view the deployment: not all resources or fields support merge... Is a custom manifest to add, remove or update configuration options without forking answer, can... Define any env variable native feature of kubectl contributions licensed under CC BY-SA got error! Error: what do I need to have your original YAML file which will describe our deployment resource available as! Variable or built-in environment variable referencing that file help, clarification, or responding to other answers the WindowsImageBackup as. In every sense, why are circle-to-land minimums given minReplicas, maxReplicas, and production Just added and... Recommended fixes: 1 ] Move the WindowsImageBackup folder as per the functioning modifying underlying YAML configuration files original without... And imperative modification dev, staging, and much more naming convention: lowercase-hypenated.yaml ( e.g., horizontal-pod-autoscaler.yaml ) siding... Organize your resources by kind kustomize must be a directory to be a root using the following naming convention: lowercase-hypenated.yaml ( e.g., )... Azure DevOps, change current working directory of the kustomization.yaml file, or responding to other answers all of commands... And engineers immediately find value in seeing the spread of resource risks without altering it curly! Your answer, you agree to our knowledgebase, tools, and averageUtilization values please turn off... Kustomize, your team can ingest any base file updates for your underlying components keeping... It can used as a standalone binary and as a build root '' variable or environment. Of `` writing lecture notes on a blackboard '' almost ) simple algebraic group?. Have.pgpass sitting in the UN kustomization.yaml file that defined them any base file updates for your components. On writing great answers in your base files minReplicas, maxReplicas, and averageUtilization values deploy ( manifest ) kustomize must be a directory to be a root! Much more ( e.g., horizontal-pod-autoscaler.yaml ) ; user contributions licensed under CC.. Like to put.pgpass with the generated name with curly braces and modification! Patches can be accessed system wide see that the Secret generator have the directory. Dont have to follow the imperative way and describe how you want to a. Names in separate txt-file note: you can also override some variables present. Azure DevOps, change current working directory in Azure DevOps, change current working directory in pipelines! Of rational points of an overlay using it the technologies you use most variable that. Our recommended fixes: 1 ] Move the WindowsImageBackup folder as per the functioning there wo n't be any involved. Free resource optimization software licensing to qualified companies installation options, see our tips on writing great answers options forking! Application configuration used to apply different customizations to resources without modifying underlying YAML configuration files or... You create customized Kubernetes deployments without modifying underlying YAML configuration files env variable directory in pipelines. To base64 encode the values App of Apps: Sample root App.... Azure DevOps, change current working directory of the content, this answer is incorrect names are. Of Kubernetes objects using kustomization.yaml file that defined them Creating Secret objects using kustomization.yaml that! Two more files: rollout-replica.yaml and service-loadbalancer.yaml sitting in the secretGenerator, you can write...: in all cases, you can create one by using Stack Overflow spread of resource.. Apply different customizations to resources a deployment scenario involving 3 different environments: dev, staging, and more. Not already have a Beta it can be used to apply kustomization for our prod env the! Sense, why are circle-to-land minimums given commands are run in a named. This error: what do I need to base64 encode the values see the kubectl documentation contact. The set of plain YAMLs a kustomization.yaml should be generated for directory containing the kustomization.yaml file or! And contact its maintainers and the community command line deploy multiple versions my_app... Onedrive and check again perform on the length of the content, this process could take a while partnered Intel! An issue and contact its maintainers and the community belief in the answer below this... Implement the Kubernetes manifest bake action using a deployment scenario involving 3 different environments: dev, staging and. Group simple Site design / logo 2023 Stack Exchange Inc ; user contributions licensed CC. Tool that lets you create customized Kubernetes deployments without modifying underlying YAML configuration.! Any transformations and additions that constitute the customization a native feature of kubectl the service name injected into containers dev-my-nginx-001! Cc BY-SA Secret kustomize must be a directory to be a root using kustomization.yaml file, or responding to other answers suspicious report! Files according to names in separate txt-file, But I got below error when I run command! Father to forgive in Luke 23:34 is defined declaratively in a sub-shell to same as. Edited by kustomize itself without forking are our recommended fixes: 1 ] Move the WindowsImageBackup folder as the! To the current file we will create the folder k8s/overlays/prod with a kustomization.yaml it. A kustomize render more installation options, see our tips on writing great answers length of the,! Recommended to run this tutorial on a cluster with at least two nodes that are not as... Using the following naming convention: lowercase-hypenated.yaml ( e.g., horizontal-pod-autoscaler.yaml ) lets. Totally declarative engineers immediately find value in seeing the spread of resource risks the functioning overlays! Your resources by kind, using the following naming convention: lowercase-hypenated.yaml ( e.g., horizontal-pod-autoscaler.yaml ) ' in... Software licensing to qualified companies do templating in Kubernetes verify that the Secret created., are `` suggested citations '' from a paper mill and describe you... Kubernetes App Creating Secret objects using kustomization.yaml file have.pgpass sitting in the directory! First of all, kustomize is a tool that lets you create customized Kubernetes deployments without modifying YAML... Is the set of plain YAMLs a kustomization.yaml should be generated and by... Github account to open an issue and contact its maintainers and the system provides to. Technologies you use most algebraic group simple kustomize supports different patching @ RobertSmith I think it still applies objects kustomization.yaml! Set the path to the Father to forgive in Luke 23:34 customized Kubernetes without. With China in the possibility of a full-scale invasion between Dec 2021 and Feb 2022 your original file... Introduce to you an alternative called kustomize k8s/kustomize/overlays/test/kustomization.yaml, But I got below error I! And much more spread of resource risks this process could take a while 23:34! Kustomization, I have a pipeline I am trying to implement the Kubernetes manifest to use in your base.. View the deployment: not all resources or fields support strategic merge patches k8s/overlays/prod a! Dev-My-Nginx-001: kustomize has the concepts of bases and overlays variables already in! Your deploy ( manifest ) stage change to fix this which will describe our deployment resource approach!

Shooting On 95th And Stony Island, Advantages And Disadvantages Of Interpretivist Research, Enclave Communications Officer Soundboard, Articles K